Typically in integrated circuit memories isolation devices have been interposed between a p-sense amplifier and a shared n-sense amplifier in the memory array. However in order to conserve die space only one p-sense amplifier may be used. In this case the isolation device is interposed between a digit line pair and the p-sense amplifier and between the digit line pair and the n-sense amplifier. In order for the p-sense amplifier to pass the full value of the charge on the digit line, the isolation device, typically an n-channel transistor, must have a gate voltage equal to the value of the charge plus a threshold voltage of the transistor. Therefore it becomes necessary to drive the potential of the gate of the isolation n-channel transistor to a pumped potential. The pumped potential is a potential elevated above the supply potential. To do this the gate is driven to a pumped supply potential by a driver circuit which is interposed between a pumped node, which has been pumped to the pumped potential, and the gate of the n-channel. However, pumping the supply potential to a pumped potential at the pumped node consumes a significant amount of power.